1. Field of the Invention
The invention relates to cooling of glass volume, such as tempering of glass plates having curvature in several directions, especially plates intended for making vehicle windows.
2. Discussion of the Background
It is known that such cooling can be achieved by means of two cooling-gas blowing chests, one lower and the other upper respectively, disposed opposite each other.
Some chests intended for tempering curved plates have a central region, on each side of which there are joined two lateral regions; because of their complexity they are cumbersome, but are capable of tempering plates of diverse geometries in the thickness range greater than about 4 mm.
Nevertheless, because of the present trend toward manufacture of increasingly thin plates with increasingly more complex forms, the differences in distances between chest and plate over the surface thereof have greater consequences, and the impossibility of sufficiently ensuring the ideal plate-to-chest distance over numerous zones of the plate surface results in internal tensions which make the plate susceptible to cracking.
Other chests xe2x80x9cdedicatedxe2x80x9d to the plate to be tempered and to plates of very similar geometry make it possible to temper plates of complex forms, but the chest must be changed whenever the type of plate is changed. Because the chests are used only during a period equal to the xe2x80x9clifetimexe2x80x9d of a type of plate, such as a rear window or side window, it is imperative to lower the prime cost thereof, although at the present time it has not been possible to reduce this price sufficiently.
In fact, these present chests are made from parts assembled either by use of threaded fasteners and bonding adhesives or by welding, all manually performed operations requiring considerable labor.
The object of the invention is to remedy these disadvantages and to provide cooling chests whose prime cost and operating costs are moderate, and which permit great precision in the cooling operation, such as tempering.
This object is achieved according to the invention by a chest for cooling and more particularly for tempering glass plates, provided with nozzles forming a blowing zone, a rigid support associated with at least one panel on which the nozzles are fixed, each nozzle comprising two flanges and a strap perforated with blow holes, and the flanges being of one-piece construction, which is provided with tabs folded toward the neighboring flanges, the fixations of the flanges to each other and of the straps to the flanges being achieved by riveting and/or interposition of a cement.
According to a preferred embodiment of the invention, and for better fixation of the nozzles, the chest is provided with at least one tie rod traversing the assembly of nozzles and the panel.
More preferably, and to minimize the deformation of the flanges, braces are slipped over the tie rod.
In a preferred variant of the invention endowing the structure with even more rigidity, the chest is provided with:
xe2x86x92a rigid support provided with two panels and two faces connecting these two panels,
xe2x86x92an assembly of nozzles disposed in succession from one panel to the other and extending from one face to the other while projecting beyond the support toward the cooling space, each nozzle being provided with two flanges and one strap perforated with blow holes inserted between the flanges along at least one edge segment thereof to comprise the blowing outlet, and fixed to the flanges by riveting, each flange being provided with tabs integral therewith, folded at right angles toward the neighboring flanges, at least some tabs being superposed and fixed together by rivets and interposition of a cement,
xe2x86x92tie rods for fixation of the assembly of nozzles to the support, traversing this assembly and the panels, and braces slipped thereover and provided between the neighboring flanges belonging to two neighboring nozzles with a surface which limits the deformation of the flanges.
By virtue of the structure that it was possible to adopt as a result of the riveting and adhesive bonding assembly process, and in particular the speed of the folding operations, the weight improvement and the reduction of the number of welds and components, the object mentioned hereinabove was successfully achieved without compromising the quality level of the product obtained by means of the device according to the invention.